Hormone Action Is Mediated by Receptors

The conversion of vitamin D3 to an active compound. Vitamin D3 is organs. The first reaction occurs in the liver and results in 

Receptors for steroid hormones are located within the cell and bind to specific DNA sequences when they are activated by the appropriate hormones. The binding of these 

Possible mechanisms of hormone action, (a) The hormone (H) theoretically activates an enzyme (E) directly as an allosteric effector. (b) Alternatively, a separate binding protein for the hormone, called a receptor (R), may then activate an enzyme, (c) Another possibility interposes an acceptor protein (A) between the receptor and the enzyme. Each interaction is reversible. 

Hormones that Activate or Inhibit Adenylate Cyclase 

Many Plasma Membrane Receptors Generate a Diffusible Intracellular Signal 

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Steroid Hormones Are Derived from Cholesterol The Circulating Hormone Concentration Is Regulated Hormone Action Is Mediated by Receptors... 

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